Q: According to Japanese media, US Defense Secretary Mattis said during his visit to Japan that the US-Japan security treaty is applicable to Diaoyu Dao. What is your comment?

A: Diaoyu Dao and the affiliated islands have been China's territory since ancient times. This is a historical fact that will not be distorted. The so-called security treaty between the US and Japan, as a product of the Cold War era, shall not undermine China's territorial sovereignty and legitimate rights and interests. We urge the US to be responsible, stop making wrong remarks regarding the sovereignty of Diaoyu Dao, and avoid further complicating the relevant issue and making the regional situation more prone to instablity.